Статті в журналах з теми "Freight cars Dynamics"
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1
Fomin, O. V., and A. O. Lovska. "Research of the Vertical Dynamics of the Supporting Structures of Freight Cars Made of Round Pipes." Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, no. 1(91) (February 15, 2021): 104–14. http://dx.doi.org/10.15802/stp2021/227223.
Повний текст джерелаАнотація:
Purpose. This study is aimed at determining the vertical dynamics of supporting structures of freight cars made of round pipes. Methodology. Mathematical modeling of the dynamic loading of the supporting structures of the main types of freight cars made of round pipes (gondola car, covered car, flat car, hopper car) was carried out. The studies were carried out in a plane coordinate system – the XZ plane. At the same time, it was taken into account that the car is moving in an elastic-viscous track so that the reactions of the track are proportional to both its deformation and the rate of this deformation. The studies were carried out for the case of empty cars. The joint inequality is described by a periodic function. The calculation was performed at a speed of 80 km/h. Differential equations of motion were solved in the MathCad software package using the Runge-Kutta method. Findings. Based on the mathematical modeling of the dynamic loading of the supporting structures of cars made of round pipes, the main indicators of their dynamics were obtained: accelerations acting on the supporting structures in the mass center, forces acting in the spring suspension of bogies, dynamics coefficients. For gondola car, covered car, and hopper car, the acceleration at the mass center of the supporting structure is within 0.4 g, and for a flat car – 0.5 g. It was found that the obtained indicators of the dynamics of cars made of round pipes are within the permissible limits. The accelerations acting on the supporting structures of cars made of round pipes are almost the same as those obtained for prototype cars. At the same time, the motion of cars is assessed as "excellent" for gondola car, covered car, and hopper car and "good" for flat car. Originality. Mathematical modeling of the dynamic loading of the supporting structures of cars from round pipes was carried out and the main indicators of their dynamics were obtained. Practical value. The research carried out will contribute to the creation of recommendations for the design of supporting structures of freight cars of round pipes, and can also be useful developments in the creation of innovative car designs.
2
Маслак and A. Maslak. "PRINCIPLES OF ESTIMATION OF OPERATIONAL PARAMETERS OF FREIGHT STATION FUNCTIONING IN TERMS OF TRANSPORT PROCESS DYNAMICS." Alternative energy sources in the transport-technological complex: problems and prospects of rational use of 2, no. 2 (December 17, 2015): 790–96. http://dx.doi.org/10.12737/19565.
Повний текст джерелаАнотація:
At present time freight stations operation is complicated by raised dynamics of production and transport processes. Under the given handling capacity, this circumstance affects duration of processing of inbound and internal flow of freight cars. New approaches to analysis, assessment of operational characteristics, and designing of freight railway stations within industrial enterprises, considering dynamics of production and transport environment, are developed.
3
Shvets, A. O. "INFLUENCE OF LATERAL DISPLACEMENT OF BOGIES ON THE FREIGHT CAR DYNAMICS." Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, no. 6(90) (April 8, 2021): 66–81. http://dx.doi.org/10.15802/stp2020/223519.
Повний текст джерелаАнотація:
Purpose. The work is aimed at determining the influence of the lateral displacement of a freight car bogie, taking into account the value of the movement speed on its main dynamic indicators and interaction indicators of the rolling stock and the track. Methodology. The quantitative assessment of dynamic indicators was obtained by the method of mathematical and computer modeling. The design scheme of the car takes into account the interaction peculiarities of cars as part of the train: the possibility of all modes of body vibration in space, the transmission of longitudinal force from neighboring cars in vertical and horizontal directions, taking into account the technical condition of individual parts of the car and their design features, as well as various operating conditions. Findings. During the research, a mathematical model of a coupling of five freight cars was applied to study the dynamic loading of a gondola car and a track. Main dynamic and interaction indicators of the rolling stock and the track in case of transverse bogie displacement when moving along curved track sections assessment were assessed. The maximum possible values of the lateral displacement of the freight car bogie were substantiated. Originality. The mathematical model of the coupling of freight cars in the train has been improved. In the calculation schemes describing the vibrations of the cars, the peculiarities of the freight car bogies, lozenging of the bogie side frames are taken into account. The model makes it possible to study the effect of changing rotation angle of the central axis of the car body, which in turn leads to the lateral displacement of bogies relative to each other, on the main dynamic and interaction indicators of the rolling stock and the track. For the first time, the influence of transverse displacement of the bogie was investigated, taking into account the wear of its parts and assemblies when moving on track sections with unevenness. Practical value. The calculation results can be used to assess the influence of the bogie transverse displacement on the dynamic qualities of the rolling stock and interaction indicators of the rolling stock and the track, taking into account the wear of parts and units of the bogie when moving in straight and curved track sections with irregularities. The application of the results obtained will contribute to an increase in the stability of freight rolling stock in the conditions of increasing travel speeds, which in turn will allow developing technical conditions for the implementation of resource-saving technologies for transporting goods that meet the safety requirements of train traffic.
4
Shevchenko, D. V., M. A. Kudryavtsev, A. M. Orlova, S. A. Ponomarev, A. M. Sokolov, and Yu V. Savushkina. "Numerical modeling of the dynamics of the clutch couplers." Vestnik of the Railway Research Institute 78, no. 3 (July 28, 2019): 155–61. http://dx.doi.org/10.21780/2223-9731-2019-78-3-155-161.
Повний текст джерелаАнотація:
One of the priorities of the program “Strategy for the development of railway transport in the Russian Federation until 2030” is the introduction and development of heavy haul traffic, allowing to ensure the increasing volume of freight traffic and significantly improve the efficiency of railways. Main challenges for scientific research and design development to ensure the creation of freight cars for heavy haul traffic, along with an increase in longterm load and decrease in tare weight, include the issue of increasing the load from the wheelset to the rails to 27 tons for heavy haul cars SA-3T and couplers SA-3. It is shown that increasing the load from the wheelset to the rails up to 27 tons while maintaining the dynamic running load within the normalized values can be achieved by increasing calculated deflection of the spring suspension of the truck, which in turn leads to an increase in the possible height difference between the couplings of adjacent cars. Authors explain necessity of putting into operation a coupler for heavy haul cars SA-3T, providing an increase in the vertical coupler contour line up to 210 mm. Regulatory documents governing the provisions of automatic coupling devices in freight cars were analyzed. Dynamic computational models have been developed that describe the behavior of automatic couplings in the process of coupling cars, taking into account the inertial characteristics of all parts included in the assembly, the geometric nonlinearity associated with their contact interaction, and the elastic-damping properties of the absorbing device. Verification of calculated dynamic model has been carried out. Numerical experiments simulating the coupling of the considered automatic coupling devices with the most unfavorable possible combinations of horizontal deviations and rotation angles were performed. It is confirmed that the developed design of the coupler CA-3T provides grip when there is a possible difference between the lower surfaces of the locks of adjacent coupler up to 210 mm both between themselves and with the typical coupler CA-3.
5
Ushkalov, V. F., and N. V. Bezrukavyi. "Study of the dynamics of freight cars with radial-type trucks." Technical mechanics 2020, no. 1 (February 27, 2020): 106–13. http://dx.doi.org/10.15407/itm2020.01.106.
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6
Sverdlov, Vadim Borisovich, and Vasiliy Fedorovich Lapshin. "Car fleet safety assurance on non-public railway tracks." Transport of the Urals, no. 4 (2021): 33–39. http://dx.doi.org/10.20291/1815-9400-2021-4-33-39.
Повний текст джерелаАнотація:
The paper considers problems connected with car fleet safety assurance, it highlights aspects that require a scientific solution. Special attention is paid to assessment of influence of railway transport structural reform on dynamics of damage growth of freight cars. The paper shows that the greatest amount of damage occurs during freight and shunting operation on non-public railway tracks while a technological level of organization and execution of freight operations on industrial enterprises can’t guarantee an exception of car damage risks. On the example of open-box cars unloading with the use of overhead vibration machines the authors have considered aspects of safety assurance that require a scientific justification. They have highlighted priority tasks that it is necessary to solve: revision of normative and technical documentation on freight car safety assurance, arrangement of interaction between car owners, a railway infrastructure owner and owners of non-public railway tracks, development of methodological basics for organization of car fleet safety assurance system.
7
Matyash, Yu I., and I. A. Gadzhiev. "Development of an onboard monitoring device for freight car shock-absorbing device’s technical condition." Vestnik of the Railway Research Institute 78, no. 4 (November 25, 2019): 218–26. http://dx.doi.org/10.21780/2223-9731-2019-78-4-218-226.
Повний текст джерелаАнотація:
Good technical condition of rolling stock is an important consideration for increasing safety in train traffi c. Safety is the state’s priority in the development and modernization of the railroad industry. The goal of this study is to develop an onboard monitoring device for a freight car’s shock-absorbing device’s technical condition. This justifi es the need to control the serviceability of the unit and the urgency to equip freight cars with onboard monitoring systems. The following tasks were set and resolved: collection and analysis of information on the dynamics of changes in the number of faults of freight cars serviced at the sites of the current uncoupling repair of Russian companies from 2008 to 2018; study the expediency of the primary control of serviceability of different units of the freight car; collection and analysis of information including statistical data, scientifi c publications, and thesis on the effect of a failed shock-absorbing device on other units of the freight car and reduction of the train’s overall traffi c safety. The study enabled development and manufacturing of a mockup onboard monitoring device freight car shock-absorbing device’s technical condition, with its functional capabilities described. To increase the diagnostics accuracy, technology defi ning failure criteria of the controlled unit and reduction of its operation effectiveness is developed. The main recommendations for using the proposed onboard device are also provided. The principal advantages of the device are underlined and reasons for freight rolling stock owners to equip their cars with the developed system are advanced.
8
Shvets, A. O. "INTERACTION DYNAMICS OF SOME TYPES OF FREIGHT CARS WITH A RAILWAY TRACK." Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, no. 5(89) (December 2, 2020): 142–59. http://dx.doi.org/10.15802/stp2020/217649.
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Egorov, Yuriy Vladimirovich, Liliya Faatovna Kazanskaya, and Nadezhda Vyacheslavovna Saks. "Influence of development of market of freight cars operation upon operation efficiency indexes of railway transport." Transportation systems and technology 3, no. 3 (September 15, 2017): 162–75. http://dx.doi.org/10.17816/transsyst201733162-175.
Повний текст джерелаАнотація:
Purpose. The article is devoted to estimation of influence of process of development of market of freight cars operation upon operation efficiency indexes of Russia’s railway transport. The existing qualified viewpoints on this issue have been considered. Methodology. For quantitative evaluation, the authors have used comparative analysis methods and econometric modeling based on JSC “RZD” and Federal State Statistics Service data of the period from 2003 till 2016. Results. According to the results of econometric modeling, it has been found out that statistically important influence of development of freight cars operation market upon indexes of operation efficiency of Russia’s railway transport is present only in one part of variable - “amount of deliveries, performed within normative (stipulated) period”. At the same time, indexes of operation efficiency of Russia’s railway transport demonstrate negative dynamics only from 2003 till 2009-12; from then on, most of these indexes have been showing sustainable positive tendency, having recovered from initial negative shock. This kind of shock might be a reaction to change of level of market development of freight cars operation in Russia, but this does not apply to all indexes of operation efficiency of JSC “RZD”.
10
Han, Hui Shi, Mei Han, and Xiao Xia Wang. "Study on Lateral Vibration Offsets of Speed Increased Freight Cars on the Tangent Track." Advanced Materials Research 779-780 (September 2013): 567–71. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.567.
Повний текст джерелаАнотація:
According to the vehicle dynamics theory, the dynamics simulation models of single-vehicle NX70H flat marked loading capacity of 70t with K5 bogies and NX70 flat marked loading capacity of 70t with K6 bogies under certain loading and running conditions were established by SIMPACK, in order to discuss the change rules of the roll angles, the yaw angles, the lateral offsets and the maximum lateral vibration offsets. Based on the statistical analysis of data calculated by SIMPACK, the results of dynamics single-vehicle models of the two wagon types running on Chinese I and III grade railway lines respectively were compared. Simulation results show that the running speed, the line condition and the height distancing the rail surface all have a significant impact on the maximum lateral vibration offset.
11
Lu, Bi Hong, Yu Zhang, Bao Zhang Qu, Jian Song Huang, and Yu Liu. "Research on RecurDyn Based Simulation Method for the Brake Shoe Eccentric Wear in Railway Freight Cars." Key Engineering Materials 522 (August 2012): 467–71. http://dx.doi.org/10.4028/www.scientific.net/kem.522.467.
Повний текст джерелаАнотація:
The foundation brake rigging is an important part of the railway freight cars, as it is an actuator of the rolling stock for deceleration and stop to ensure essential device for running safety. The mechanism clearance of the foundation brake rigging has a great influence on the brake shoe eccentric wear in the braking and releasing process. Especially during the braking process, the contact area between the brake shoe and the wheel tread is very small, resulting in the contact area with high stress. Actual operation manifests that on the upper side of the brake shoe wear severely. In order to build and analyze the model of the mechanism with clearance, the foundation brake rigging for the rigid-flexible coupling and multi-body dynamics simulation is carried out with the RecurDyn software, which provides the flexible body analysis module-FFlex. The method of resolving the problem is proposed, which includes the original model format conversion, the model preprocessing, constructing the rigid-flexible coupling dynamics model and analyzing the simulation results, and then providing the theoretical and technical support to improve the foundation brake system for railway freight cars by analyzing the main factors of influencing brake shoe eccentric wear.
12
Fomin, O., S. Kara, P. Prokopenko, M. Gorbunov, and V. Fomin. "EVALUATION OF DYNAMIC QUALITIES OF MOVEMENT OF RE-EQUIPPED HOPPER CARS OF PILS OF LONG-TERM OPERATION." Collection of scientific works of the State University of Infrastructure and Technologies series "Transport Systems and Technologies", no. 36 (December 30, 2020): 33–42. http://dx.doi.org/10.32703/2617-9040-2020-36-4.
Повний текст джерелаАнотація:
As part of the work, a theoretical and experimental study (based on running dynamic tests) of the running qualities of empty hopper cars, converted from cement trucks and mineral trucks, was conducted. Computer simulation of the dynamics of empty hopper wagons converted from cement and mineral wagons depending on the condition of the track, the technical condition of the wagons and the weight of the container, the repeated presence of maximum vertical deviations and horizontal deviations of the track. A significant disadvantage of the railway transport of Ukraine is the limitation of the speed of trains with individual freight cars in an empty state, which are equipped with carts model 18-100. Among the reasons for the descent of the wheels of cars from the rails are: malfunctions of the running gear of the cars (fracture of the side frames and spring beams of the carts, malfunctions of the roller bearings of the axle box), wear of friction damper elements, unacceptable deviations and upgrades. As part of the work, a theoretical and experimental study (based on running dynamic tests) of the running qualities of empty hopper cars, converted from cement trucks and mineral trucks, was conducted. Computer modeling of the dynamics of empty hopper wagons, converted from cement and mineral wagons depending on the condition of the track, the technical condition of the wagons and the weight of the container and studies of the dependence of the wheel stability on the east.
13
Batig, А. V., and A. Ya Kuzyshyn. "NECESSITY TO IMPROVE THE MATHEMATICAL MODEL OF FREIGHT CARS TO STUDY CASES OF ITS DERAILMENTS." Criminalistics and Forensics, no. 65 (May 18, 2020): 442–51. http://dx.doi.org/10.33994/kndise.2020.65.43.
Повний текст джерелаАнотація:
One of the most important problems that pose a serious threat to the functioning of railways is the problem of freight cars derailment. However, according to statistics, the number of cases of the derailments of freight cars in trains annually grows. Тo prevent such cases, the necessary preventive measures are developed, and to study the causes of their occurrence, a significant number of mathematical models, programs and software systems created by leading domestic and foreign scientists. Studies of such mathematical models by the authors of this work have led to the conclusion that they are not sufficiently detailed to the extent that it is necessary for analyze the reasons of its derailment. At the same time, an analysis of the causes of the rolling stock derailments on the railways of Ukraine over the past five years showed that in about 20 % of cases they are obvious, and in 7 % of cases they are not obvious and implicitly expressed. The study of such cases of rolling stock derailment during an official investigation by the railway and during forensic railway transport expertises requires the use of an improved mathematical model of a freight car, which would allow a quantitative assessment of the impact of its parameters and rail track on the conditions of railway accidents. Therefore, taking into account the main reasons that caused the occurrence of such railroad accidents over the last five years on the railways of Ukraine, the article selected the main directions for improving the mathematical model of a freight car, allowing to cover all the many factors (explicit and hidden) and identify the most significant ones regarding the circumstances of the derailment rolling stock off the track, established on the basis of a computer experiment. It is proposed in the mathematical model of a freight car to take into account the guiding force, the value of which is one of the main indicators of the stability of the rolling stock. The authors of the article noted that not taking into account the influence of the guiding forces on the dynamics of the freight car can lead to an erroneous determination of the reasons for the rolling stock derailment or even to the impossibility of establishing them.
14
Sidorova, E. A., V. O. Pevzner, and A. I. Chechel’nitskiy. "Indicators of the force interaction of the track and rolling stock when a freight car runs on long irregularities, taking into account the action of longitudinal forces." VNIIZHT Scientific Journal 80, no. 6 (December 27, 2021): 359–65. http://dx.doi.org/10.21780/2223-9731-2021-80-6-359-365.
Повний текст джерелаАнотація:
Authors describe formation mechanism of long irregularities of the railway track and the importance of their elimination for the track facilities. Based on the results of freight train operation modeling on long irregularities in the traction mode, an analysis of the processes occurring during the motion of heavy trains along a track with such deviations was carried out, modeling was carried out on the basis of the “Universal Mechanism” software package. Based on the results of the calculation, interaction between the track and the rolling stock in the vertical plane was assessed in terms of the magnitude of the vertical force and coeffcients: dynamics, stability margin, Nadal, unloading (in percent) of axle springs of freight car springs. Article analizes the nature of the infuence of the irregularity slope on the decrease in the vertical force transmitted from the wheel to the rail and the change in the traction force on the dynamics of freight cars in the train and passing on long irregularities of the longitudinal profle through the indicators of the vertical force.
15
Zhang, Yue, and Dongping Wang. "Numerical Analysis of the Aerodynamic Characteristics of the Open Line Intersection of Fast Freight Train with the Speed of 160 km/h." Journal of Physics: Conference Series 2125, no. 1 (November 1, 2021): 012014. http://dx.doi.org/10.1088/1742-6596/2125/1/012014.
Повний текст джерелаАнотація:
Abstract With the increase of the speed of fast freight train, the aerodynamic effect of freight train in open-line intersection is more obvious. However, at present, there are many domestic researches on the aerodynamic characteristics of high-speed train open-line intersection, and almost no researches on fast freight train. Therefore, it is of great significance to study the aerodynamic characteristics of open line intersection of fast freight train in order to improve the safe operation of freight train in China. Based on the theory of computational fluid dynamics and finite volume method, uses FLUENT software to numerically calculate the three-dimensional, unsteady, compressible and turbulent flow fields in open line intersection of fast freight train at different speeds. The calculations results indicate that: when two freight trains meet, the amplitude of the pressure wave at the intersection side is the largest and the closer to the train bottom, the greater the amplitude of the pressure wave. The pressure amplitude of the bottom measuring point is 34.09% higher than that of the top measuring point. When two cars intersect at the same speed, the higher the speed, the greater the pressure amplitude and the pressure amplitude is proportional to the square of the speed. The fitting formula is: ΔP = cV2 ; When two trains intersect at different speeds, the impact on freight train with lower speed is greater than higher one.
16
Qu, Bao Zhang, Hong Bo Zhang, Bi Hong Lu, and Zhen Ming Liu. "Research on Brake Shoe Eccentric Wear Mechanism by Analytical Method and Virtual Experiment." Key Engineering Materials 620 (August 2014): 318–23. http://dx.doi.org/10.4028/www.scientific.net/kem.620.318.
Повний текст джерелаАнотація:
In this paper, a theoretical mechanical model for the brake shoe is set up according to the foundation brake unit of railway freight cars, and it indicates that the friction moment is the origin resulting in brake shoe eccentric wear. On this basis, the pressure distribution formula on the brake shoe is derived when the train brakes in forward and backward direction respectively. The analysis results show that if the wheel and the brake shoe are concentric, the ratio of the revolving-in end pressure to the revolving-out end pressure in wheel forward revolving is larger than that in wheel backward revolving. It is consistent with the phenomena that upper eccentric wear often appears on the brake shoe in practice. Further research reveals that the degree of the eccentric wear is determined by the braking force action style, which is the theoretical basis for the design revision. In addition, the RecurDyn Multi-body Dynamics software is used to build the rigid-flexible coupling dynamics model for the foundation brake unit. The simulation experiment verified the analysis result. The research outcome provides the theoretical basis and technical support for further design improvement of the foundation brake unit in railway freight cars.
17
Anisimov, P. S. "DYNAMIC FEATURES OF STANDARD TANK CARS ON CURVED TRACK SECTIONS." World of Transport and Transportation 14, no. 1 (February 28, 2016): 22–31. http://dx.doi.org/10.30932/1992-3252-2016-14-1-2.
Повний текст джерелаАнотація:
[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT Nature of interaction of wheel sets of four-axle and eight-axle tank cars with rails when driving in curves of railway track is considered, including specifics of longitudinal and transverse elastic ties of wheel sets with bogie’s side frames. The results of dynamic performance studies (coefficient of dynamic addition of vertical forces on sprung weight and transverse frame force) of tank cars in curves with radii of 350 and 650 m are provided. It follows that eight-axle tank car design under the terms of traffic safety from the point of view of dynamics is at the same level as a four-axle one, therefore, can be used without restriction on all railways under the same rules of maintenance for undercarriages of tank cars of both types. Keywords: railway, theoretical mechanics, tank car, wheel sets, rails in curves, dynamic performance, elastic and frictional bonds, unextinguished transverse acceleration, coefficient of dynamic addition of vertical forces, frame force, comparative analysis. REFERENCES 1.Verigo, M. F.Interaction of track and rolling stock in curves of small radius and the fight against side wear of rails and wheel flanges [Vzaimodejstvie puti i podvizhnogo sostava v krivyh malogo radiusa i bor’ba s bokovym iznosom rel’sov i grebnej koljos]. Moscow, PTKB CP MPS publ., 1997, 207 p. 2. Anisimov, P. S. Methods of Evaluation of the Impact of Freight cars on the Track. World of Transport and Transportation, Vol.12, 2014, Iss.1, pp.24-32. 3.Vershinskiy, S.V., Danilov, V.N., Khusidov, V. D. The dynamics of the car [Dinamika vagona]. Moscow, Transport publ., 1991, 360 p. 4.Anisimov, P.S., Zhelnin, G.G., Kulikovskiy, B. S. Permissible speed of eight-axle tanks dimensions TC [Dopuskaemye skorosti dvizhenija vos’miosnyh cistern gabarita Tc]. Trudy MIIT, 1986, Iss.780, pp.10-24. 5.Anisimov, P.S., Grachiova, L. O. Tests of eight-axle tanks for BAM [Ispytanija vos’miosnyh cistern dlja BAMa]. Zheleznodorozhnyj transport, 1986, Iss.5, pp.35-36.
18
Tarmaev, A. A., G. I. Petrov, and V. N. Filippov. "Analysis of freight cars wheels wear based on mathematical modeling of the dynamics of their movement." Journal of Physics: Conference Series 1172 (March 2019): 012087. http://dx.doi.org/10.1088/1742-6596/1172/1/012087.
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Zhai, W. M., Q. C. Wang, Z. W. Lu, and X. S. Wu. "Dynamic effects of vehicles on tracks in the case of raising train speeds." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 215, no. 2 (March 1, 2001): 125–35. http://dx.doi.org/10.1243/0954409011531459.
Повний текст джерелаАнотація:
In order to enhance the efficiency of railway transportation, Chinese Railways has decided to raise the speed of trains on the existing railway main lines. A theoretical model and the corresponding simulation software, VICT, based on the vehicle-track coupling dynamics are employed to analyse dynamic effects of trains on track structures caused by raising train speeds. Chinese passenger cars and freight cars running on the lines where speed has been raised were chosen for investigation. It is shown that raising train speeds on the existing railway lines obviously intensifies the dynamic effects of vehicles on tracks, especially in the turnouts, in the welded rail joints, and in the sections of bridge-subgrade connections. The occurrence of wheel flats becomes more general after raising train speeds. An unfavourable peak of dynamic effects of wheel flats on tracks is observed in the speed range from 140 to 160 km/h, which is just the region of running speeds for passenger trains after the increase in the speed. Some basic countermeasures, including stricter maintenance standards for the speed-raised railways, are proposed to solve these problems, on the basis of dynamic analysis.
20
Ko, Sangpil, Pasi Lautala, and Kuilin Zhang. "Data-Driven Study on the Sustainable Log Movements: Impact of Rail Car Fleet Size on Freight Storage and Car Idling." Sustainability 12, no. 11 (June 3, 2020): 4563. http://dx.doi.org/10.3390/su12114563.
Повний текст джерелаАнотація:
Rail car availability and the challenges associated with the seasonal dynamics of log movements have received growing attentions in the Lake Superior region of the US, as a portion of rail car fleet is close to reaching the end of its service life. This paper proposes a data-driven study on the rail car peaking issue to explore the fleet of rail cars dedicated to being used for log movements in the region, and to evaluate how the number of cars affects both the storage need at the sidings and the time the cars are idled. This study is based on the actual log scale data collected from a group of forest companies in cooperation with the Lake State Shippers Association (LSSA). The results of our analysis revealed that moving the current log volumes in the region would require approximately 400–600 dedicated and shared log cars in ideal conditions, depending on the specific month. While the higher fleet size could move the logs as they arrive to the siding, the lower end would nearly eliminate the idling of rail cars and enable stable volumes throughout the year. However, this would require short-term storage and additional handling of logs at the siding, both elements that increase the costs for shippers. Another interesting observation was the fact that the reduction of a single day in the loading/unloading process (2.5 to 1.5 days) would eliminate almost 100 cars (20%) of the fleet without reduction in throughput.
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Markova, O. M., M. V. Sobolevska, T. F. Mokrii, and D. V. Horobets. "Increasing the safery of railway passenger and freight traffic." Technical mechanics 2021, no. 2 (June 29, 2021): 78–90. http://dx.doi.org/10.15407/itm2021.02.078.
Повний текст джерелаАнотація:
In 2020, the Ukrainian Government conducted an audit of the Ukrainian economy for nearly 30 years of independence and decided on the vectors of economic development aimed at European and Euro-Atlantic integration. The audit of the Ukrainian railways showed that most of the railway assets are critically worn. The audit and the vectors became a starting point for the development of the National Economic Strategy of Ukraine up to 2030, which was approved on March 3, 2021. One of the priorities of this strategy is the development of the transport sector by a succession of steps, including railway track and vehicle renewal, the introduction of high-speed passenger transport, and increasing railway traffic safety and environment safety on the Urrainian railways. The aim of this paper is to work out recommendations on increasing the safety of passenger and freight traffic in Ukraine. The paper generalizes the experience gained over the years of Ukrainian independence in the fundamental and applied transport-oriented reseach conducted at the Department of Sttistical Dynamics and Multidimensional Mechanical Systems, Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine. This experience may be useful in the implementation of the above steps on the way to the sustainable development of the Ukrainian railway transport. In the paper, emphasis is on new investigations into the passive propection of the cars of a motor car train in emergency collisions whose scenarios are specified by Ukrainian State Standard DSTU EN 15227. Based on a mathematical model of a collision of identical motor car trains, a mathematical model was developed to simulate a collision of a motor car train with a large vehicle at a crossing with account for a specified force characteristic of interaction of the leading car equipped with a passive safety system with a deformable obstacle. The model developed was used in analyzing dynamic loads on the cars of a motor car train with a passive safety system in its collision at 110 km/h with a 15 t large vehicle at a railway crossing. With consideration for the results of previous investigations into the dynamics of emergency collisions of a motor car train with an identical train and a fright car, recommendations were worked out on the passive protection of a home-made leading car in accordance with the requirements of normative documents. The proposed mathematical models and designs of energy-absorbing devices, the research results, and the practical recommendations worked out may be used in designing new motor car train vehicles for the Ukrainian railways in accordance with the DSTU EN 15227 requirements for passive protection in emergency collisions.
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Mankevych, N. B. "Dynamics of freight cars on bogies model 18-1711 with different wedge de-signs of spring suspension." Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, no. 1(49) (March 11, 2014): 142. http://dx.doi.org/10.15802/stp2014/22686.
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Fomin, O. V., and A. O. Lovska. "Determination of vertical dynamics for a standard Ukrainian boxcar with Y25 bogies." Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, no. 5 (2020): 67–72. http://dx.doi.org/10.33271/nvngu/2021-5/067.
Повний текст джерелаАнотація:
Purpose. To determine the basic dynamic characteristics of a standard Ukrainian boxcar with the Y25 bogie by means of the mathematic modelling of dynamic loads in the vertical plane and to compare them with the dynamic characteristics obtained for a boxcar with the 18100 bogie. It can be used for substantiation of application of the Y25 bogie as more promising, which can improve the operational efficiency of rail transportation and foster integration of the Ukrainian transport system into the European transportation complex. Methodology. The authors used the mathematical modelling of a boxcar with the Y25 bogie. The research was made in the vertical plane. It was taken into account that an empty car passed over a joint irregularity. The research was made for an 11217boxcar as a predominant type to be used. The authors studied the motion of a car on the 18100 and Y25 bogies. The basic dynamic characteristics were determined for a boxcar with the nominal (design) dimensions of the carrying elements and a boxcar with the actual dimensions (after a long service life) on the basis of the field tests. The differential equations were solved by theRungeKutta method in MathCad software suite. The initial displacements and the speeds were taken equal to zero. The following dynamic characteristics of a boxcar were obtained: acceleration of the body in the center of mass, acceleration of the body in the areas of support on the bogies, forces in the spring suspension of the bogie, and dynamic coefficients of the bogies. Findings. The theoretical research showed that the basic dynamic characteristics of a boxcar with the nominal dimensions were improved by 3851% in comparison to a similar one with the 18100 bogie, and for a boxcar with the actual dimensions the dynamic characteristics were improved by 4350%. Originality. The authors substantiated the application of the Y25 bogie for a standard Ukrainian boxcar with the nominal and actual dimensions of the carrying elements by means of the mathematical modelling of the dynamic loads in the vertical plane. Practical value. Due to lower dynamic loads on the carrying structures of freight cars with the Y25 bogie, it is possible to improve the dynamic characteristics of the structures under the operational modes, to increase the fatigue strength and the operational resource, to decrease the total repair and maintenance costs, to ensure better security and reliability of freight transportation through lower loads on both carrying structures and lashing devices, to increase the speed of freight delivery thanks to better dynamic characteristics of cars, to improve the traffic security, and so on.
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Pevzner, V. O., A. I. Chechel’nitskiy, K. V. Shapet’ko, E. A. Sidorova, and A. Yu Slastenin. "Influence of long irregularities of the longitudinal profile on traffic safety under conditions of intensification of the transportation process." VNIIZHT Scientific Journal 79, no. 5 (November 10, 2020): 271–75. http://dx.doi.org/10.21780/2223-9731-2020-79-5-271-275.
Повний текст джерелаАнотація:
The key directions of intensification of the transportation process are described and their influence on the infrastructure is indicated. The concept of long irregularities of the longitudinal profile is defined and a method is proposed that allows one to study the geometric parameters and the growth rate of long irregularities. An assessment of the influence of long irregularities on energy consumption during the traction of trains is given.In the article, much attention is paid to the influence of long irregularities of the longitudinal profile on traffic safety. The article presents the results of the state analysis of the railway track section, where there was a derailment of the freight cars. The results of calculations of the level of forces arising in the automatic coupling and the coefficients of the vertical dynamics of the first stage of suspension for cars in a train when moving uphill along long irregularities are presented. Based on the results of the research, the main conclusions are formulated and the direction of further research is proposed.
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Zhao, Yong Xiang, Bing Yang, Ming Fei Feng, Y. Li, M. J. Liu, and Guo Xiang Song. "Probabilistic Critical Fatigue Safety State of the RD2 Type Axle of China Railway Freight Car." Advanced Materials Research 44-46 (June 2008): 751–58. http://dx.doi.org/10.4028/www.scientific.net/amr.44-46.751.
Повний текст джерелаАнотація:
Critical fatigue safety state is investigated on RD2 type axle of China railway freight cars. Attention is paid on the grooves near axle boxes, where more fatigue cracks were early appeared even result in at least six derailed accidents. Load history was obtained by vehicle dynamics simulation combining with on-line inspection. Braking loads and effects of maintenance and off-round of wheels are also incorporated. Semi-elliptical and external circumferential cracks are employed for crack growth simulation. Crack shape change and shear stressing of the semi-elliptical crack are taken into account. New crack growth rate modeling in which covers from cracking threshold to toughness related fracture state is applied for residual life evaluation. Critical fatigue safety state is defined as the crack size from which the axle can be safely operated to next overhaul inspection. Critical crack size is estimated step-by-step with the crack shape change. Results show that the external circumferential crack is more dangerous than the semi-elliptical crack. Application more than two years in production verifies that the present assessment is available and reliable.
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Domin, R. "METHOD OF OPERATIONAL INVESTIGATION OF ROLLING STOCK DERAILMENT." Collection of scientific works of the State University of Infrastructure and Technologies series "Transport Systems and Technologies" 1, no. 37 (June 29, 2021): 173–86. http://dx.doi.org/10.32703/2617-9040-2021-37-17.
Повний текст джерелаАнотація:
The article presents the principles of the method of operational investigation of rolling stock derailment. This method is intended to identify the most significant mechanical reasons for transport accidents in order to find directions to further improving the safety requirements for the state of maintenance of freight cars and tracks on the basis of the data. The developed method establishes a general methodological order of conducting computer simulation of the dynamics of rolling stock of multivariate studies on calculating the safety indicators of train’s motion, and shows the significance of technical factors that provoked a certain event. By this method, the operational investigation of rolling stock derailment is based on the development of adequate computer models of dynamics of cars in trains. In this case, in detail, all the features of the car, which descended from the rails, are first. The presented method is based on the principles of factor analysis, where the intervals of varying events are presented in natural units of measurement. In this case, the assessment of security indicators for each research of the experiment plan is also carried out taking into account their dimension. As a result, the function of multiple regressions on the chosen indicator of motion safety allows not only to determine the significance of the factor of the ascent, but also to establish the level of factors, with exceeding the criteria for motion safety, that is, to determine the boundaries of the region with an acceptable level of motion safety.
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Rudavsʹkyy, D. V., M. S. Shefer, Yu I. Kanyuk, Z. Ya Shpak, and N. S. Ripak. "Calculation model for the evaluation of tired defect development in the freight wagon side frame." Ukrainian Journal of Information Technology 3, no. 2 (November 23, 2021): 15–20. http://dx.doi.org/10.23939/ujit2021.02.015.
Повний текст джерелаАнотація:
The reliability and safe operation of mechanical elements of rail transport is an important and relevant scientific and technical issue since high-loaded units and elements of its chassis are exposed to prolonged operation and their failure can lead to damage with catastrophic consequences. To prevent the possible failure of such objects, there is a necessity for a reliable estimation of their residual life. Among the cast parts of the freight car trolley, the side frames are one of the most loaded elements, which take on dynamic loads that cause vibrations of the unsprung parts of the freight car. The side frame of the 18-100 trolley, as a typical representative of a number of trolleys of freight cars, does not have a sufficient margin of resistance to fatigue and survivability, so it is sensitive to some deviations and defects (different wall thickness, sinks, and pores, residual stresses) that are detected during the operation process. Based on the energy approach of the mechanics of materials fatigue failure, the calculation models for estimating the dynamics of the development of crack-like defects under the action of operational load are developed in this work. The calculation models constructed using modern information technologies, and the software developed for their numerical implementation allow predicting the impact of irregular cyclic loading and complex stress on the growth of surface fatigue crack in the side frame of the carriage, which significantly brings the problem closer to real operating conditions. Numerical calculations were performed using a computer program of our own development in the Python programming language. At the first stage of the program functioning the spectrum of amplitudes of irregular cyclic loading is built, at the second - the program module of numerical solution construction for systems of usual differential equations of the proposed mathematical model of fatigue defect development is started. Calculations of the fatigue crack growth dynamics taking into account the action of shear stresses in the section with the crack of the side frame showed a slight effect of shear stresses on the residual durability of the frame. It is demonstrated that the dynamics of surface crack development significantly depend on its initial geometry. The proposed calculation method for determining the initial shape of the surface crack with a minimum period to critical growth can be effectively used to predict the residual durability during the technical diagnosis of the running gear parts of railway rolling stock. Keywords: wagon side frame; fatigue crack; probability distribution function; load amplitude spectrum; numerical method.
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Bolshakov, Roman Sergeevich, Andrey Pavlovich Khomenko, and Sergey Victorovich Eliseev. "New approaches of condition estimation of freight railway carriages at motion on sorting devices on base system analysis and mathematical modeling." Transport of the Urals, no. 4 (2021): 24–32. http://dx.doi.org/10.20291/1815-9400-2021-4-24-32.
Повний текст джерелаАнотація:
The paper develops methods of system analysis and technologies for control dynamic conditions of technical means of railway transport. Methods of structural mathematical modeling are used, within the framework of which the design scheme of the object, considered as a mechanical oscillatory system with several degrees of freedom, is interpreted as a dynamically equivalent automatic control system. The problems of the dynamics of the coupling of two freight railway carriages with two variants of its rigidity (conventional and rigid hinge-type fastening) are considered. It is shown that with a certain choice of the values of the moments of inertia of the railway carriages and the parameters of the location of the center of mass, it is possible to solve the problems of motion stabilization. Concepts are proposed for the experimental determination of the moment of inertia and coordinates of the center of mass of the railway carriage when rolling the cars off the marshalling hump and passing a special measuring station. Algorithms for determining the values of the parameters of the center of mass of the railway carriage and the values of the moment of inertia are proposed.
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Cagliano, Anna Corinna, Antonio Carlin, Giulio Mangano, and Carlo Rafele. "Analyzing the diffusion of eco-friendly vans for urban freight distribution." International Journal of Logistics Management 28, no. 4 (November 13, 2017): 1218–42. http://dx.doi.org/10.1108/ijlm-05-2016-0123.
Повний текст джерелаАнотація:
Purpose The purpose of this paper is to investigate the diffusion dynamics of electric and hybrid commercial vans and its enabling factors in the city logistics (CL) contexts. The case of parcel delivery in Torino, Italy, is considered. Attention is paid to the influence on the choice of low impact vehicles of not only public strategies but also operational aspects characterizing urban freight distribution systems. Design/methodology/approach A System Dynamics model based on the Bass diffusion theory computes the number of adopters of low-emission vehicles together with the quantity of vans required and the associated economic savings. The model includes variables about freight demand, delivery frequency, van carrying capacity, routes, stops, distances traveled, and vehicle charging stations. A sensitivity analysis has been completed to identify the main diffusion levers. The focus is on advertising and other drivers, such as public contributions, taxes traditional polluting vehicles are subjected to, as well as on routing optimization strategies. Findings Advertising programs, green image, and word-of-mouth drive market saturation, although in a long time period. In fact, low-impact vehicles do not offer any economic advantage over traditional ones requiring higher investment and operating costs. Public incentives to purchase both green vehicles and charging stations, together with carbon taxes and a congestion charge affecting polluting vehicles, are able to shorten the adoption time. In particular, public intervention reveals to be effective only when it unfolds through a number of measures that both facilitate the use of environmentally friendly vehicles and discourage the adoption of traditional commercial vans. Route optimization also hastens the complete market saturation. Research limitations/implications This work fosters research about the mutual relationships between the diffusion of low-emission commercial vehicles and the operational and contextual CL factors. It provides a structured approach for investigating the feasibility of innovative good vehicles that might be part of assessments of CL measures and requirements. Finally, the model supports studies about the cooperation among stakeholders to identify effective commercial vehicle fleets. Practical implications This study fosters collaboration among CL players by providing a roadmap to identify the key factors for the diffusion of environmentally friendly freight vehicles. It also enables freight carriers to assess the operational and economic feasibility of adopting low-impact vehicles. Finally, it might assist public authorities in capturing the effects of new urban transportation policies prior to their implementation. Originality/value Most of the current CL literature defines policies and analyzes their effects. Also, there are several contributions on the diffusion of low emission cars. The present study is one of the first works on the diffusion of low-impact commercial vehicles in urban areas by considering the associated key operational factors. A further value is that the proposed model combines operational variables with economic and environmental issues.
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SHIMANOVSKY, Alexandr O., Marina G. KUZNIATSOVA, and Volha U. DZEMYANCHUK. "COMPUTER MODELING OF INTERACTION DYNAMICS OF THE RAILWAY CAR WHEELSET WITH BRAKING SHOES." Mechanics of Machines, Mechanisms and Materials 4, no. 57 (December 2021): 48–55. http://dx.doi.org/10.46864/1995-0470-2021-4-57-48-55.
Повний текст джерелаАнотація:
The paper considers the problem of keeping cars from rolling away on station railway tracks with a permissible slope of 0–2.5 ‰. The study presents the computer simulation results for the dynamic interaction of wheels with brake shoes installed on rails in the process of stopping a freight train car using standard brake shoes in the MSC.ADAMS engineering software package. In this case, various properties of the rail surface were taken into account, simulating favorable and unfavorable conditions for contact between the wheel, brake shoe and rail at braking due to both weather conditions and the peculiarities of station tracks location and operation. The interaction of the car wheels with the maximum axle load and the station brake shoes installed on the rails was studied at different initial velocities of the vehicle movement, as well as when it is at rest on tracks with the permissible slope under the conditions of ensuring the minimum friction between the wheel and the rail, as well as the interaction of rail and shoe was analyzed, which corresponds to the presence of the train on oily rails. It is demonstrated that it is not always possible for one brake shoe put on the oily rail to hold the train moving with the initial velocity more than 0.5 m/sec. Under other conditions of the wheel-brake shoe collision, the problem of keeping the train on the rails is also possible, due to such random factors as lateral wind load, rail icing, wear and deformation of the wheel surface and brake shoe, which reduce the dynamic friction coefficient between the contacting surfaces.
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Savchenko, Lidiia, Miroslava Semeriahina, and Irina Shevchenko. "Modeling daily dynamics of speed and fuel consumption for urban delivery means." Electronic Scientific Journal Intellectualization of Logistics and Supply Chain Management #1 2020 9 (October 2021): 31–43. http://dx.doi.org/10.46783/smart-scm/2021-9-3.
Повний текст джерелаАнотація:
Road transport is one of the most important elements of the functioning of a modern city. Maneuverability, mobility, speed of delivery of goods and other criteria have provided him with a special and leading place in urban logistics. However, along with the benefits of a developed transport network for society, its progress is accompanied by negative consequences for the environment and the population of the city. High rates of growth in the number of cars, especially in large cities, cause an increase in emissions of harmful products into the atmosphere, which, accordingly, negatively affects the health of the population. Consequently, the problem of environmental pollution in large cities from harmful emissions from vehicles requires an urgent solution. The increase in emissions of harmful substances is affected by an increase in the consumption of fuel materials due to a decrease in speed because of an increase in traffic density in the city. The frequency, duration, prevalence of congestion is increasing along with the urbanization of the population and the increase in the number of cars in cities. The dense development of the central historical districts of the city exacerbates the problem of unhindered passage of individual, public and freight vehicles. In addition, a decrease in the speed of city traffic affects the speed of delivery of goods, correspondence, etc., which negatively affects the speed of business processes, and ultimately worsens the level of logistics services for customers. The purpose of this study is to analyze the current situation in terms of the dynamics of the average speed of the city's traffic flow by hours of the day and to obtain a mathematical model of the dependence of the speed of movement on the consumption of fuel materials for various environmentally friendly means of urban delivery (car, motorcycle, bicycle and pedestrian courier). The research was carried out in two stages. At the first, the study of the dependence of the average speed of movement in the city on the time of day (for all means of city delivery) was carried out. At the second stage, the study of the dependence of the average consumption of fuel materials in the city (which, accordingly, is a function of the speed of movement) on the time of day for motorized urban delivery vehicles was done. In the course of the study, at each stage, an equation of the trend lines was obtained with a sufficient approximation accuracy. In conclusion, the study proposes an algorithm for determining the average speed and average amount of fuel consumption when delivering small consignments in an urban environment using four urban logistics means - a car, a motorcycle, a bicycle, and a pedestrian courier (with the possibility of using public transport). The proposed algorithm can be applied in any delivery conditions in the city.
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Shabel’Nikov, A. N., and Yu V. Shapovalova. "Modeling of maintenance systems for railway infrastructure facilities based on the theory of mass service." Vestnik of the Railway Research Institute 77, no. 3 (June 28, 2018): 165–71. http://dx.doi.org/10.21780/2223-9731-2018-77-3-165-171.
Повний текст джерелаАнотація:
The article is substantiated the necessity of intro-and dynamics of change are proposed to be implemented within ducing the mechanism of predictable maintenance of railway trans-the framework of a specially created decision support system. It port infrastructure into the practice of the transportation process. was also proposed to use the mathematical apparatus of queuing The functions of object monitoring, diagnostics of their condition theory to implement the tasks of analyzing and synthesizing the structure and functions of the system for organizing maintenance of transport infrastructure facilities. Within the framework of this tool, a mathematical model for the synthesis of maintenance systems for railway infrastructure facilities was constructed and analyzed, and a network of queuing systems describing monitoring, diagnostics and maintenance of these facilities was considered. The analysis technique of the infrastructure objects includes the procedure for structuring the railway transport object in the form of a combination of queuing systems and queuing networks, analysis of their parameters, analysis and optimization of information flows in queuing networks. The features of the application of the developed model for the solution of three practical problems are analyzed: technical and commercial inspection of trains at the sorting station reception, identification and correction of wheelset defects on thermal anomalies, development of a system for diagnosing the negative dynamics of freight cars. A model is described that allows calculating the main parameters (service intensity, service time and location in network) for a network that includes the source of applications (the transportation process), the diagnostic subsystems (as part of the decision support system - DSS) and the maintenance depoes.
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BRZHEZOVSKIY, A. M. "On the rationing the parameters of asymmetric loading of all-purpose freight cars." Vestnik of the Railway Research Institute 78, no. 2 (June 5, 2019): 82–89. http://dx.doi.org/10.21780/2223-9731-2019-78-2-82-89.
Повний текст джерелаАнотація:
Due to the presence in the operating fleet of freight cars with a base of over 10 m, as well as the practical impossibility of symmetrically placing loads with a weight corresponding to the nominal carrying capacity on open rolling stock, adjustments to the existing asymmetrical loading standards are necessary. To this end, it is proposed to apply a comprehensive methodology for determining the allowable parameters of asymmetrical placement of freights, based on a combination of strength criteria of the bearing elements of cars, ensuring the normative level of dynamic qualities and stability of the loaded car. The article provides an example of determining the permissible parameters of the joint lateral and longitudinal displacement of the total center of gravity of the car (ЦТгр°), loaded to the nominal capacity. According to the results of the studies to determine the allowable values of longitudinal and lateral displacement ЦТгр° with unbalanced placement within the loading platform of the car, including the presence of a joint displacement, it was found that to improve the efficiency of using freight cars with an increased base, it is advisable to update the current offset standards of ЦТгр°. It is recommended to take the values of longitudinal displacement ЦТгр° for cars with a body base of 14.6 and 19.0 m respectively 1.46 and 2.11 m for freight with a total weight of 50 tons; 1.10 and 1.43 m for freight with a total weight of 60 tons; 0.22 and 0.28 m – for freight with a total weight of 67 tons. When placing freights with a total weight of over 67 tons with a height of center of gravity of 2.0–2.2 m on 4-axle freight cars with an axle load of 230.5 kN without limiting the permissible driving speeds, it is recommended to use a graphical method for determining the joint (longitudinal and transverse) displacement ЦТгр°. With an increase in the joint displacement parameters ЦТгр°, it will be necessary to limit the speed of the car in the curved sections of the track and to the lateral direction on the turnouts.
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Shi, Huailong, Liang Wang, Brynne Nicolsen, and Ahmed A. Shabana. "Integration of geometry and analysis for the study of liquid sloshing in railroad vehicle dynamics." Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 231, no. 4 (March 1, 2017): 608–29. http://dx.doi.org/10.1177/1464419317696418.
Повний текст джерелаАнотація:
A new continuum-based liquid sloshing approach that accounts for the effect of complex fluid and tank-car geometry on railroad vehicle dynamics is developed in this investigation. A unified geometry/analysis mesh is used from the outset to examine the effect of liquid sloshing on railroad vehicle dynamics during curve negotiation and during the application of electronically controlled pneumatic (ECP) brakes that produce braking forces uniformly and simultaneously across all cars. Using a non-modal approach, the geometry of the tank-car and fluid is accurately defined, a continuum-based fluid constitutive model is employed, and a fluid-tank contact algorithm is developed. The liquid sloshing model is integrated with a three-dimensional multibody system (MBS) railroad vehicle algorithm which accounts for the nonlinear wheel/rail contact. The three-dimensional wheel/rail contact force formulation used in this study accounts for the longitudinal, lateral, and spin creep forces that influence the vehicle stability. In order to examine the effect of the liquid sloshing on the railroad vehicle dynamics during curve negotiation, a general and precise definition of the outward inertia force is defined, and in order to correctly capture the fluid and tank-car geometry, the absolute nodal coordinate formulation (ANCF) is used. The balance speed and centrifugal effects in the case of tank-car partially filled with liquid are studied and compared with the equivalent rigid body model in curve negotiation and braking scenarios. In particular, the results obtained in the case of the ECP brake application of two freight car model are compared with the results obtained when using conventional braking. The traction analysis shows that liquid sloshing has a significant effect on the load distribution between the front and rear trucks. A larger coupler force develops when using conventional braking compared with ECP braking, and the liquid sloshing contributes to amplifying the coupler force in the ECP braking case compared to the equivalent rigid body model which does not capture the fluid nonlinear inertia effects. Furthermore, the results obtained in this study show that liquid sloshing can exacerbate the unbalance effects when the rail vehicle negotiates a curve at a velocity higher than the balance speed.
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Petrov, S. V., I. V. Nazarov, and O. N. Nazarov. "Holistic model of the formation of requirements for freight cars on the example of the “Northern Latitudinal Railway” project." VNIIZHT Scientific Journal 79, no. 5 (November 10, 2020): 251–60. http://dx.doi.org/10.21780/2223-9731-2020-79-5-251-260.
Повний текст джерелаАнотація:
In the context of economic integration, an important factor is increasing the efficiency of rail transport. It depends both on the quality of the transportation process as a whole and on the quality of its individual elements. It is especially worth highlighting the rolling stock, and in particular freight cars, since it is with the car along the route that labor-intensive technological operations are performed, including shunting, technical and commercial maintenance, unscheduled repairs, as well as starting and finishing operations — loading and unloading. Therefore, the efficiency of freight transportation does not depend to a small extent on the quality of cars.In this regard, the article highlights the results of the development of a holistic model for the formation of requirements for freight cars that increase the efficiency of the transportation process, taking into account the features of specific transportation conditions. In this case, a holistic model is applied to the conditions for the export of freights from fields in Western Siberia along the routes of the Northern Latitudinal Railway project.A holistic model for the formation of requirements for the cars of the Northern Latitudinal Railway includes:• operational and functional model, containing the substantiation of the technical and economic parameters of the cars and the model of their operation ranges, taking into account the technological operations performed;• reliability model containing justification of the reliability indicators of cars and the parameters of the system of their maintenance and repair;• model for evaluating and confirming efficiency based on the results of calculating a complex of technical and economic indicators of cars.The holistic model makes it possible to formulate rational requirements for cars of different levels of specialization for specific operating conditions. The model also makes it possible to predict the effects of participants in the transportation process when using cars with given characteristics in specific transportation conditions. This contributes to the use of the principles of dynamic pricing of tariffs, depending not only on the type of freight and the region, but also on the route, distance of transportation and other parameters. As a result, the advantages and competitiveness of rail transport will be provided.
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Hou, Yi Meng, and Qi Zhang. "Research on Information Processing with Release Method of Railway Freight Loading Information Based on Dynamic Planning Model." Advanced Materials Research 977 (June 2014): 480–83. http://dx.doi.org/10.4028/www.scientific.net/amr.977.480.
Повний текст джерелаАнотація:
Freight loading information can not only limit the cargo volume from customers but also guide them to arrange their freight reasonably. This paper analyzed the factors influencing release of railway freight loading information, and established a freight loading information release model based on dynamic planning by setting the most important two indexes -- quantity of freight cars and equilibrium degree of freight cars as objective functions. The model was proved to be effective in balancing daily freight workload on the premise of satisfying customers’ requirements on cargo loadings. Thereby, the author thinks that reasonable release of freight loading information is effective and efficient in making more profits with limited resources.
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Brzhezovskiy, A. M., O. A. Krasnobaev, A. V. Spirov, and I. E. Il’in. "On the permissible speeds of empty freight cars mounted on 18-100 model bogies." VNIIZHT Scientific Journal 80, no. 2 (June 1, 2021): 65–75. http://dx.doi.org/10.21780/2223-9731-2021-80-2-65-75.
Повний текст джерелаАнотація:
Problem of ensuring motion safety of empty freight cars is most acute in relation to cars on bogies of model 18-100, which is mainly due to operational wear of wheelsets, side frames and bolsters, as well as spring suspension elements. A potential threat to traffic safety arises when a train, composed of mostly empty and lightly loaded cars, moves along track sections that have deviations in the geometry of rail track of III and higher degrees or combinations and sequences of deviations of II degree. The article presents the main results of complex studies: mathematical modeling of the dynamic interaction of the track and empty freight cars of various types of bogie wear based on the Universal Mechanism software and field tests of cars on measuring sections of tangent, easement and circular curves with a radius of 350, 650, 800, 1000 and 2050 m on the section Belorechenskaya — Maykop of the North Caucasian railway. Dynamic qualities and motion stability of empty freight cars of various types are investigated depending on the parameters of the technical condition of the running gears and the deviations of the geometry of the rail track of II and III degrees of various types and combinations when moving in tangent and curved track sections. Authors provide tables and graphs of the dependences of indicators of dynamic qualities and motion stability of universal empty freight cars of various types on the motion speed in tangent sections of the track and circular curves of various radii and easement curves containing artificial deviations of the geometry of the rail track, most negatively affecting traffic safety. Recommendations are given for correcting the regulatory documents of the Russian Railways, which regulate the permissible speed of motion of empty freight cars, depending on the technical condition of the running gear.
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Martynenko, Liubov. "Assessment of the technical condition of rolling stock and track in order to improve traffic safety." E3S Web of Conferences 363 (2022): 01059. http://dx.doi.org/10.1051/e3sconf/202236301059.
Повний текст джерелаАнотація:
The basic task of the work was to conduct the research aimed at studying the technical condition of the track and its impact on the rolling stock since the car dynamics, especially in curves and on the mountain pass sections of the track, is completely dependent on track deviations. The real time data received from specialized car laboratories show the existence of deviations visually detected, however external deviations are not crucial since the main problem lies inside the structure with changes already taking place in the layers of the subgrade not reflected externally, still affecting the movement of the rolling stock, especially the cars already having permissible technical deviations in operation. The technical condition of the track is directly related to the subgrade and ballast layer therefore the research is aimed at studying the lower base of the track in order to identify defects and malfunctions limiting the speed of the rolling stock and posing a constant threat to the safety of the transportation process. The main task is to identify and study the technical deviation of the subgrade layers, which directly affects the safety of the rolling stock, especially with an increase in freight traffic. The article proposes a method for evaluating GPR sounding of the subgrade, which sees into the depth of the soil up to 8 meters, depending on the equipment used. A theoretical study of the influence of the subgrade on the derailment of the rolling stock due to the deformation of the rail-sleeper grid allows to find the cause of deviations in the dynamics of the car when passing through the corresponding section. This article contains a quantitative and qualitative analysis obtained as a result of a research based on which comprehensive measures were developed to ensure traffic safety. At present, the operation of railways requires increased safety, an increase in the speed of rolling stock and the throughput of the main railway network. With regular inspections at the wagon laboratories, a better study of the track and subgrade is obtained through regular monitoring. Due to the complex of measures for diagnosing the track, a qualitative assessment of the performance of individual operations and the timely detection the railway track faults, as well as subsequent repairs according to the actual state of the track, are carried out.
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Zhao, Ce, Lixing Yang, and Shukai Li. "Allocating Freight Empty Cars in Railway Networks with Dynamic Demands." Discrete Dynamics in Nature and Society 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/349341.
Повний текст джерелаАнотація:
This paper investigates the freight empty cars allocation problem in railway networks with dynamic demands, in which the storage cost, unit transportation cost, and demand in each stage are taken into consideration. Under the constraints of capacity and demand, a stage-based optimization model for allocating freight empty cars in railway networks is formulated. The objective of this model is to minimize the total cost incurred by transferring and storing empty cars in different stages. Moreover, a genetic algorithm is designed to obtain the optimal empty cars distribution strategies in railway networks. Finally, numerical experiments are given to show the effectiveness of the proposed model and algorithm.
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Yi, Bing, Renkai Sun, Liu Long, Yongfeng Song, and Yinggui Zhang. "From coarse to fine: an augmented reality-based dynamic inspection method for visualized railway routing of freight cars." Measurement Science and Technology 33, no. 5 (February 16, 2022): 055013. http://dx.doi.org/10.1088/1361-6501/ac3c1c.
Повний текст джерелаАнотація:
Abstract The dynamic inspection of railway routes for freight cars transporting cargo that is out of gauge is a challenge. One possible way is using the inspection frame installed in the inspection train to simulate the whole procedure for cargo transportation, which requires a lot of manpower and material resources as well as time. To overcome the above problem, this paper proposes an augmented reality-based dynamic inspection method for visualized railway routing of freight cars with out-of-gauge cargo. First, an envelope model of the dynamic moving train with out-of-gauge cargo is generated using the orbital spectrum of the railway, and the envelope model is matched with a piece of homemade calibration equipment located at the position of the railway that needs to be inspected. Then, the structure from motion algorithm is used to reconstruct the environment where the virtual envelope model occludes the buildings or equipment along the railway. Finally, the distance function is adopted to calculate the distance between the obstacle and the envelope of the out-of-gauge freight car, determining whether the freight car can pass a certain line. The experimental results show that the proposed method performs well for the route selection of out-of-gauge cargo transportation with low cost, high precision, and high efficiency. Moreover, the digital data of the environments along the railway and the envelope of the freight car can be reused, which will increase the digitalization and intelligence for route selection of out-of-gauge cargo transportation.
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Razhepaeva, F. Z. "Сrimean Tatars: deportation and fate of the people in Kazakhstan". BULLETIN of the L.N. Gumilyov Eurasian National University. Historical sciences. Philosophy. Religion Series 137, № 4 (2021): 92–106. http://dx.doi.org/10.32523/2616-7255-2021-137-4-92-106.
Повний текст джерелаАнотація:
The article is devoted to an urgent and insufficiently studied problem. It is the deportation of the Crimean Tatars to Kazakhstan during the Great Patriotic War. The author presented a historiographic review of the literature on the forcible resettlement of certain ethnic groups to the territory of Kazakhstan, which showed the lack of today works entirely devoted to the Crimean Tatars, who, at the behest of the leadership of the totalitarian state, ended up in Kazakhstani lands. In this regard, the purpose of this article was to disclose the process of deportation and residence in the conditions of special settlements of the Crimean Tatars during the war and in the post-war period in Kazakhstan. The author introduced into scientific circulation the materials of the State Archives of the Almaty Region, the Central State Archives of the Republic of Kazakhstan, the State Archives of the Karaganda Region, and the Archives of the President of the Republic of Kazakhstan, published in various collections of materials and documents. The article discusses the reasons for the resettlement of the Crimean Tatar ethnos to the East, shows how the betrayal and desertion of individual people were blamed on the whole people, as the country’s leadership for the security of its southern borders, within two days they carried out an operation to send old people in freight cars, women and children to the eastern lands. Part of the Crimean Tatars ended up in Kazakhstan. The author, relying on documents and archival materials, examines the resettlement of «Crimeans» in Kazakhstani lands, their living in special settlements, the lack of rights and freedoms, the possibility for children of deported Crimean Tatars to master only technical specialties necessary for the development of the economy of the Kazakh SSR. The number of «Crimeans», their knowledge of their native language, was witnessed by the data of the 1970 and 1999 population censuses, which the author cites in the article in dynamics and in comparison. In the conclusion, the conclusion is presented that, despite all the difficulties of the fate of the whole people, the Crimean Tatars were able to adapt and actively engage, together with representatives of other ethnic groups, in the creative work for the development of Kazakhstan.
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Domin, Yurii V., Rostyslav Yu Domin, Ganna Yu Cherniak, and Volodymyr S. Nozhenko. "Analysis of the conditions for the exhaustion of the stability margin in the rail track of freight cars with three-piece bogies." Archives of Transport 57, no. 1 (March 31, 2021): 119–29. http://dx.doi.org/10.5604/01.3001.0014.8042.
Повний текст джерелаАнотація:
The research on improvement of methodical approaches to definition of the probable reasons of infringement of conditions of stability of freight cars from derailment is carried out. Using a basic computer model of the dy-namics of a freight car, the influence of the characteristics of the technical condition of their running gear and track on the indicators of empty cars stability from derailment was studied through the computational experi-ment. The article presents the main statements of the research methodology, which provides the analysis of probable causes of derailment of freight cars by conducting a series of numerical experiments with logging the progress of calculations and saving the results. Factor analysis was used to interpret the calculated data with an assessment of each of the factors influence or their combination on the probability of derailment. The developed procedure of the simulation experiment provides a step-by-step study of the freight cars derail-ment conditions, including factors structuring and ranking, development of experimental plan, calculating coef-ficients of wheel pairs resistance to derailment from rails, provided that the wheel flange rolls onto the rail head, and determining the degree of influence of relevant factors on the dynamic stability of cars from derailment. A comparative analysis of the stability of cars in rail tracks was performed using the introduced concept of the combined coefficient of stability of wheel pairs against derailment. Determining the probable causes of car derailment is based on scanning the parameter field. The results of the parametric study revealed the degree of influence on the freight cars stability of running gear technical condition characteristics. In particular, it is determined that the most dangerous in terms of stability loss of empty cars in the track is the exceeding of the wedges of the vibration dampers.
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Gadzhimetov, G. I., G. I. Petrov, Yu A. Panin, and I. E. Il’in. "On the issue of choosing vertical and horizontal connections in a bogie for freight cars of high-speed trains." VNIIZHT Scientific Journal 79, no. 6 (February 27, 2021): 351–59. http://dx.doi.org/10.21780/2223-9731-2020-79-6-351-359.
Повний текст джерелаАнотація:
To increase the competitive advantages of rail freight transportation, the long-term development program of the Russian Railways provides for an increase in the speed of freight trains. The design speed of freight cars currently operating on the railway network is mainly 120 km/h, and the permitted speed is limited to 90 km/h. One of the possible solutions to the problem is the introduction of freight cars with an increased speed. At JSC “VNIIZHT” and JSC “VNIKTI”, work is being carried out on the selection of structures, the development of safety requirements, theoretical and experimental studies of freight traffic at increased speeds. In 2017—2018 at the Belorechenskaya—Maikop high-speed test range of the North Caucasian Railway, specialists of JSC “VNIIZHT” carried out running tests of a prototype of a platform car for transporting containers with a design speed of 160 km/h, developed by JSC “VNIKTI”. In the design of the platform car, a bogie is used, which is an analogue of the bogie of trailed cars of electric trains ED4 and ED9, with the selection of the stiffness of the springs in the spring suspension steps to comply with the difference in the level of the automatic coupler from the rail head in the “container” and “gross” modes. Analysis of the results of running tests allows determining the ways to improve the design of the bogie. To select design solutions for the purpose of ensuring safety, a review of the studies of domestic scientists aimed at studying the dynamic properties of railway rolling stock with various designs of the carriage part was carried out. Tests were carried out on prototypes of rolling stock having different elastic-dissipative connections in the “body-bogie-wheelsets” system. Based on the results of the analysis, design solutions have been determined that allow achieving satisfactory dynamic qualities for a freight car at a speed of up to 140 km/h. The adopted design solutions were tested on the basis of the results of theoretical studies of the dynamic properties of a platform car with a new bogie, carried out by the method of computer simulation. Increasing the flexibility of the spring suspension and the horizontal connection of the body with the bogie made it possible to improve the dynamic qualities of freight cars. To assess the safety during certification, it is required to develop a standard that would take into account the design features of car bogies, designed for increased speed.
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Bhatti, M. H., V. K. Garg, and K. H. Chu. "Dynamic Interaction Between Freight Train and Steel Bridge." Journal of Dynamic Systems, Measurement, and Control 107, no. 1 (March 1, 1985): 60–66. http://dx.doi.org/10.1115/1.3140708.
Повний текст джерелаАнотація:
The dynamic responses of a railway steel bridge due to vehicle-track-bridge interaction were investigated for the effects of vertical and lateral track irregularities, approach track quality, vehicle weight and type, and train speed. It was found that (1) greater approach irregularities produce higher impact factors and dynamic forces in bridge members; (2) light weight and empty cars produce higher impact factors but small dynamic forces; and (3) impact factors depend on such parameters as axle spacing, suspension system stiffness, truck center distances, etc.
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Panchenko, Sergii, Oleksij Fomin, Glib Vatulia, Alyona Lovska, Oleksandr Bahrov, Dmytro Fedosov-Nikonov, and Andrij Rybin. "Defining patterns in the dynamic load and strength of the bearing structure of a covered freight car with a filler in the girder beam." Eastern-European Journal of Enterprise Technologies 6, no. 7 (114) (December 21, 2021): 68–76. http://dx.doi.org/10.15587/1729-4061.2021.243866.
Повний текст джерелаАнотація:
This paper reports a study into determining the dynamic load and strength of the bearing structure of a covered freight car under operational modes. A feature of the freight car's bearing structure is that the girder beam has a closed cross-section. To reduce the dynamic load of the frame, the girder beam is filled with a material with viscoelastic properties. Such a solution could contribute to the transformation of the kinetic energy of impact (due to jerk, stretching, compression) into work of viscoelastic friction forces, and, consequently, to reducing the load on the bearing structure. To substantiate the proposed improvement, the dynamic load on the bearing structure of a covered freight car was mathematically modeled. The calculation was performed for the case of joint impacts at shunting. The study was carried out in a flat coordinate system. It was established that the maximum accelerations acting on the bearing structure of a covered freight car were about 37 m/s2. The calculated acceleration value is 3.2 % lower than that obtained for the bearing structure of a covered freight car without filler. The results of calculating the strength of the load-bearing structure of a covered freight car are given. In this case, a finite-element method was applied. The maximum equivalent stresses occur in the zones of interaction between the girder beam and the pivot beams, and amount to 319.5 MPa, which is 8 % lower than permissible. The calculation was also performed regarding other operational modes of loading the freight car's bearing structure. The model of the dynamic load on the bearing structure of a covered freight car was verified according to the F-criterion. The research reported here could contribute to designing innovative rolling stock structures, thereby improving the efficiency of their operation.
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Yao, Jianjun, Yuxuan Huang, Guilin Jiang, Shuang Gao, Rui Xiao, and Han Yu. "Design and its characteristic analysis of a wheeled train uncoupling robot with multi-degrees-of-freedom." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 230, no. 10 (April 9, 2015): 1673–84. http://dx.doi.org/10.1177/0954406215582017.
Повний текст джерелаАнотація:
Freight trains play a vital role in cargo transportation in the world. The freight cars need to be redistributed for marshalling according to different destinations in the hump yard. Humans are usually employed to uncouple the freight cars in the marshalling yard. However, the work environment is difficult to work in, because of its potential danger and the effects of the surrounding environment can have a very serious impact on human’s health. A wheeled robot is developed to replace humans to finish the uncoupling task. It has four degrees-of-freedom with flexible motion. Based on the D-H method, the kinematics, including the forward and the inverse kinematics, is firstly analysed. The dynamic analysis is then studied by Newton–Euler equations. The workspace is lastly investigated to verify its operational space such that the coupler can be easily reached by the robot manipulator. Those characteristic analyses provide a basis for motion planning and real-time control of the robot.
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Solonenko Vladimir Gelevich,, Makhmetova Narzankul Musaevna,, Nikolaev Victor Alexandrovich,, Kvashnin Mikhail Yakovlevich,, Bekzhanova Saule Ertaevna,, Bazanova Inna Amandykovna,, and Malik Arman Aydinovich,. "MODELING THE INFLUENCE OF THE ARTICLE DEVICE ON DYNAMIC INDICATORS OF FREIGHT WAGONS." NEWS of National Academy of Sciences of the Republic of Kazakhstan 5, no. 443 (October 15, 2020): 181–87. http://dx.doi.org/10.32014/2020.2518-170x.119.
Повний текст джерелаАнотація:
The article investigates the dynamic performance of a freight car with an articulation device - model SAC-1 RUS. As a criterion for assessing dynamic indicators, the acceleration of the car body and the dynamic deflections of the "spring-truck" system were selected, which characterize the ride and loss of stability of the car when it goes off the rails on various irregularities of the track. When an articulated car moves along different path irregularities, the acceleration that occurs at various points along the length of the car is not the same. In compiling the system of differential equations of motion of the "spring - truck" system, the Lagrange equation of the second kind was used as the mathematical apparatus. The body acceleration and the dynamic deflections of the springs were chosen as the criteria for assessing the running properties of the cars. The first characterizes the smoothness of the carriage, and the second characterizes the stability of the wheel, i.e. wheel derailment. It is known that the magnitude of the acceleration at different points along the length of the car is not the same, since the value of the vertical acceleration of bouncing is influenced by the vertical oscillations of the body's galloping. Therefore, when solving the system of differential equations, the body accelerations were determined at two points: above the center plates of the bogies and the center plate of the device for articulating freight cars or above the wheelsets, that is, in the places where acceleration sensors are installed during full-scale tests of cars. Based on the analysis of the results obtained, it was revealed that articulated cars: exclude the possibility of relative vertical displacements of adjacent cars, with other equal dynamic parameters; lead to a noticeable deterioration in driving properties, accompanied by an increase in the value of vertical acceleration of the body. The values of accelerations and dynamic deflections of an articulated car are 6% higher than those of a four-axle freight car. The vertical acceleration of the front and rear of an articulated car is 30% greater than that of a typical car. Outside the critical speed for an articulated car, the value of vertical dynamic deflections significantly decreases in the case of an isolated irregularity with a length of 6 m or less.
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Martinov, Igor, Alyona Trufanova, and Vadim Shovkun. "Construction of the simulation model “car-railway track” for modeling the dynamic loading process of the boot node." MATEC Web of Conferences 230 (2018): 01008. http://dx.doi.org/10.1051/matecconf/201823001008.
Повний текст джерелаАнотація:
Using of software systems in the design of new samples is increasingly important, but there is a problem in adapting computer models to obtain adequate results of calculations. The modern development of the IT systems gives the opportunity to significantly reduce the timing of the introduction of new equipment into production by reducing the number of field experimental test samples of the design technology. Every year using of complexes software in designing new samples is becoming increasingly important, but there is a problem in adapting computer models to obtain adequate results of calculations. UM Universal Mechanism complex was used to simulate the dynamic loading process of the boot node. Modelling of dynamic loadings on the running gears of freight cars showed a sufficient convergence with the results of running tests, about 87%. Therefore, the proposed model can be used for assessing of disturbing loads when the calculating of the reliability of the bucket units of freight cars was done.
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Zhao, Yong Xiang, Bing Yang, Ming Fei Feng, Y. Li, M. J. Liu, and Guo Xiang Song. "Probabilistic Critical Safety Wheel Wear Sizes of Chinese Railway Freight Cars." Advanced Materials Research 44-46 (June 2008): 759–64. http://dx.doi.org/10.4028/www.scientific.net/amr.44-46.759.
Повний текст джерелаАнотація:
Critical safety wheel wear size is investigated through considering the fatigue safety effect on RD2 type axle of China railway freight cars. The wheel wear size increase results in a rise of the wheel-rail contact forces, which increase the fatigue stress history of the axle in service. Therefore, the size must be controlled to maintain the axle safety in service before the next overhaul inspection. A field investigation was firstly made on the wear size change regularity. Then, the size related wheel-rail impact forces are solved by a non-linear Hertzian contact theory with a vehicle multi-body dynamic model. In addition, a statistical method is further developed for incorporating the impact forces into the wheelset service load history. Finally, a wear size related critical state equation is established for ensuring the axle safety in service. A stationary solution is statistically obtained for the critical wear sizes with respect to the axle circumferential crack and semi-elliptical crack. It is concluded that the critical safety wear size should be controlled in the range of 100 mm at the statistical level of survival probability 0.99 and confidence 95%.
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Panchenko, S., O. Fomin, G. Vatulia, A. Lovska, S. Deryzemlia, and A. Rybin. "JUSTIFICATION OF FILLERS USING IN THE BEARING STRUCTURES COMPONENTS OF FREIGHT CARS." Collection of scientific works of the State University of Infrastructure and Technologies series "Transport Systems and Technologies" 1, no. 38 (December 24, 2021): 5–13. http://dx.doi.org/10.32703/2617-9040-2021-38-5-1.
Повний текст джерелаАнотація:
To reduce the load on the freight cars frames under operational conditions, it has been suggested that to use fillers in their components. Fillers using is advisable in the most loaded elements of the bearing structure, namely, the spine beam. Therefore, a necessary condition for filler using in the spine beam is the creation of its closed structure. The dynamic load of railcars was carried out, taking into account the proposed provisions. Calculations have shown with filler using, the maximum accelerations acting on the bearing structures of wagons are 4% lower than those accelerations obtained for bearing structures without fillers. The results of determining the main strength indicators of bearing structures of freight cars are presented, taking into account the fillers using in their components. It has been established that the strength of the frames of the considered types of wagons under the main operating conditions is ensured. At the same time, the maximum equivalent stresses in the bearing structures of wagons are 4-9% lower than those in typical frame structures. The conducted research will contribute to the creation of innovative structures of rolling stock and reduce the cost of its maintenance work in operation.